Drainage element for the wire of a paper making machine



Jan. 12, 1965 1.. B. JORDANSSON 3,155,440,

DRAINAGE ELEMENT FOR THE WIRE OF A PAPER MAKING MACHINE Filed Feb. 21, 1962 FIG.I.

INVENTQOR LARS BENGT JORDANSSON (flu-M 7:0, @141 $9 051 Hus ATTORNEYS United States Patent once 3,165,440 DRAENAGE ELEMENT FOR THE OF A PAPER MAKING MACHINE Lars Bengt .lordansson, Karlstad, Sweden, assignor to Alrtieholaget Karlstads Mekaniska Werlrstad, Karlstad, Sweden, a company of Sweden Filed Feb. 21, 1962, er. No. 174,863 Claims priority, application Sweden, Feb. 23, 1961, 1,887/1961 3 Claims. (Cl. 162352) The present invention relates to a drainage element for the drainage of the forming wire of a Fourdrinier paper making machine, consisting of a stationary bar extending below the wire essentially in the transverse direction thereof and having a horizontal face over which the wire is meant to slide, and an adjoining downwardly slanting face which forms an angle of the order of l to 5 degrees to the horizontal plane.

Due to the wear caused by the wire, the upper face of the drainage bar is gradually worn off, the horizontal part thereof getting longer and longer, whereas the length of the slanting partas measured in the direction of travel of the wire-decreases, involving a reduction of the draining effect. In order to eliminate said drawback the bar must be replaced by a new one or reground regularly.

The object of the invention is to make it possible to use drainage bars during longer time periods without having to regrind them.

Said object is fulfilled by a particular design of the drainage bar consisting therein, that a flat lower face of the bar, which is disengageably applied toa support, forms an equally great angle to either of'the said top faces of the bar, so that after the bar has been disengaged, turned about to shift its ends and reattached to the support, the formerly slanting face will be horizontal and the formerly horizontal face will be set at the same angle to the horizontal plane as the angle previously taken up by the first-mentioned face.

A preferred'embodiment of the drainage bar according to the invention will be more closely described below with reference to the accompanying drawing. FIGS. 1, 2 and 3 are cross-sections of the bar showing the same in different stages of wear.

In the drawing, 11 designates the drainage bar, v 13 a stationary support therefor, and 15 the horizontally running wire of a Fourdrinier paper making machine, which slides against the upper face of the drainage bar. The bar 11 is of a length somewhat greater than the width of the wire and extends below the wire at right angles to the direction of travel of the same. Usually several drainage bars are arranged parallelly and close to each other between the breast roll of the paper making machine and its suction boxes.

The top face of the bar comprises a horizontal face 17 over which the Wire slides, and a slanting face joining the first-mentioned face and extending therefrom in the direction of travel of the wire, the angle of inclination of said latter face to the horizontal plane being of the order of 1 to 5 degrees. The fore edge 21 of the bar is inclined obliquely downwardly, so that an edge directed opposite to the direction of travel of the wire is formed, by means of which water clinging to the under side of the wire is scraped off. In the acute gap between the face 19 and the running wire a vacuum is formed, by means of which such water as is contained in the paper web and/or in the meshes of the wire is sucked out and delivered to said face or scraped off by a following bar.

The bar consists of any suitable material which is softer than the wire, so that the latter is not worn too severely, but the unavoidable wear mainly works upon the bar which is easier and cheaper to replace. FIG. 1 shows the appearance of the bar shortly after having been ,7 taken in use. Then .the'horizontal face 17 forms ap proximately a third of the entire upper face of the bar, and the slanting face 19 forms the remaining-two thirds. When the bar has been worn as much as shown in FIG. 2, the horizontal face is about twice as large as before and the slanting face is reduced to about half the earlier size. Then the draining effect has dropped too far, and the original condition of FIG. 1 must be restored in one way or other.

According to the invention, said object is realized by removing the barll, turning it endwise and reinserting the same, thereby bringing the bar into the position of FIG. 3, in which the side 21 formerly facing backwardly is facing forwardly. r

A flat bottom face 23 of the bar rests upon a flat'top I face 25 of the support 13. Said faces 23, 25 are inclined in the same direction as the face 19 but form an angle 1 /2 to the horizontal plane which is merely half as great as the angle v of inclination of said face'19. Thus, the face 23 forms equally great angles to the faces 17 and 19. As a consequence thereof, the face 19 will be truly horizontal after the endwise turning and reattachment of the bar in the position of FIG. 3, whereas the formerly horizontal face 17 now will be set in the same angle to the horizontal plane as previously the face 19. Thus, in the position of FIG. 3 the bar has the same appearance as in FIG. 1, the only difference being that the bar has been worn thinner and also slightly narrower.

-The opposite faces 21, 22 of the bar, facing forwardly and backwardly respectively, as referred to the direction of travel of the wire, form the same angle to the bottom face 23 and also the same angle to the'adjoining faces 17 and 19, respectively, or" the top face of the bar. Therefore, after shifting the ends of the bar, the scraping-01f edge of the bar, facing opposite to the direction of travel of the wire, will be set in the same angle as earlier.

The bar may be attached to the support in any suitable manner. In the embodiment shown in the drawing, the

upper side of the support 13 forms a wedge 27 of a symmetrical dovetail-shaped cross-section, which projects into a similarly shaped groove cut out of the bottom face of the bar and extending in the length direction thereof.

Due to said attachment the bar is guided in such a manner that it can be removed merely by being extracted in its length direction. Said attachment safeguards a truly correct position of the bar and makes the endwise turning of the bar rather convenient.

As is shown in FIG. 3 by dash-dot lines, by repeated order to compensate the wear it may be necessary to raise the support 13, so that the top face of the bar is maintained at the proper level relatively to the path of the wire.

I claim:

1. A device for draining the wire of a paper making machine, comprising a bar to be disposed below the wire and substantially transversely thereof, said bar having a first flap upper face, an adjoining second fiat upper face inclined at an angle of about 1 to 5 degrees to said first face, a support for said bar, a lower face on said bar inclined to saidfirst face at an angle equal to one-half the angle of inclination of said second face to said first face, said support having an upper complementally inclined face engaging said lower face of said bar and supporting said bar with said first upper face parallel with and engaging said wire and said second upper face slanting away from said wire, and means detachably connecting said bar to said support to enable said bar to be detached.

from said support, turned end for end and reattached to said support to dispose said second face parallel to said wire and said first face slanting away from said wire.

2. The drainage element set forth in claim 1 in which Patented Jan.

u) said bar has opposite side faces disposed at substantially equal angles to and diverging outwardly from said lower face of said bar.

3. The drainage element set forth in claim 1 in which the means detachably connecting said bar to said support comprises a rib of symmetrical dovetail cross-section extending upwardly from said face on said support and a substantially complemental groove in said lower face of said bar for receiving said rib.

4 References Cited by the Examiner UNITED STATES PATENTS 2,717,540 9/55 Planer 162-452 3,017,930 1/62 Dunlap l62-352 3,027,940 4/62 Dunlap 162-352 DONALL H. SYLVESTER, Primary Examiner.

MORRIS O. NOLK, Examiner. 

1. A DEVICE FOR DRAINING THE WIRE OF A PAPER MAKING MACHINE, COMPRISING A BAR TO BE DISPOSED BELOW THE WIRE AND SUBSTANTIALLY TRANSVERSELY THEREOF, SAID BAR HAVING A FIRST FLAP UPPER FACE, AN ADJOINING SECOND FLAT UPPER FACE INCLINED AT AN ANGLE OF ABOUT 1 TO 5 DEGREES TO SAID FIRST FACE, A SUPPORT FOR SAID BAR, A LOWER FACE ON SAID BAR INCLINED TO SAID FIRST FACE AT AN ANGLE EQUAL TO ONE-HALF THE ANGLE OF INCLINATION OF SAID SECOND FACE TO SAID FIRST FACE, SAID SUPPORT HAVING AN UPPER COMPLEMENTALLY INCLINED FACE ENGAGING SAID LOWER FACE OF SAID BAR AND SUPPORTING SAID BAR WITH SAID FIRST UPPER FACE PARALLEL WITH AND ENGAGING SAID WIRE AND SAID SECOND UPPER FACE SLANTING AWAY FROM SAID WIRE, AND MEANS DETACHABLY CONNECTING SAID BAR TO SAID SUPPORT TO ENABLE SAID BAR TO BE DETACHED FROM SAID SUPPORT, TURNED END FOR END AND REATTACHED TO SAID SUPPORT TO DISPOSE SAID SECOND FACE PARALLEL TO SAID WIRE AND SAID FIRST FACE SLANTING AWAY FROM SAID WIRE. 